Connect to namespace in EIO=4

[joelzavala]

Hi, I am trying to connect to a namespace in SocketIOclient using EIO 4.

So far I was able to connect to the default namespace ("/") using EIO 4 and it works great and I was even able to send an authorization.

The problem is when connecting to a namespace. What I do is this

case sIOtype_CONNECT:
        {
            Serial.printf("[IOc] Connected to url: %s\n", payload);

            // join default namespace (no auto join in Socket.IO V3)
            String data = "40/switch,{\"device\":\"";
            data += serial;
            data += "\"}";
            socket.send(sIOtype_CONNECT, data);
        }
            break;

When I run it, it prints this ( I activated debug )

[WS-Client] connect ws...
[WS-Client] connected to 192.168.1.75:4000.
[WS-Client][sendHeader] sending header...
[WS-Client][sendHeader] handshake GET /socket.io/?EIO=4&transport=polling HTTP/1.1
Host: 192.168.1.75:4000
Connection: keep-alive
origin: http://192.168.1.80
User-Agent: arduino-WebSocket-Client

[write] n: 168 t: 1512047
[WS-Client][sendHeader] sending header... Done (21690us).
[WS-Client][handleHeader] RX: HTTP/1.1 200 OK
[WS-Client][handleHeader] RX: Access-Control-Allow-Origin: *
[WS-Client][handleHeader] RX: Content-Type: text/plain; charset=UTF-8
[WS-Client][handleHeader] RX: Content-Length: 96
[WS-Client][handleHeader] RX: Date: Mon, 08 Feb 2021 23:43:35 GMT
[WS-Client][handleHeader] RX: Connection: keep-alive
[WS-Client][handleHeader] RX: Keep-Alive: timeout=5
[WS-Client][handleHeader] Header read fin.
[WS-Client][handleHeader] Client settings:
[WS-Client][handleHeader]  - cURL: /socket.io/?EIO=4
[WS-Client][handleHeader]  - cKey: Sv0F7QyBpaxlkYxYn7hlQw==
[WS-Client][handleHeader] Server header:
[WS-Client][handleHeader]  - cCode: 200
[WS-Client][handleHeader]  - cIsUpgrade: 0
[WS-Client][handleHeader]  - cIsWebsocket: 0
[WS-Client][handleHeader]  - cAccept:
[WS-Client][handleHeader]  - cProtocol: arduino
[WS-Client][handleHeader]  - cExtensions:
[WS-Client][handleHeader]  - cVersion: 0
[WS-Client][handleHeader]  - cSessionId:
[WS-Client][handleHeader] still missing cSessionId try socket.io V3
[WS-Client][handleHeader] socket.io json: 0{"sid":"ipvzuEETbfI-_H_lAAja","upgrades":["websocket"],"pingInterval":25000,"pingTimeout":5000}
[WS-Client][handleHeader]  - cSessionId: ipvzuEETbfI-_H_lAAja
[WS-Client][handleHeader] Header read fin.
[WS-Client][handleHeader] Client settings:
[WS-Client][handleHeader]  - cURL: /socket.io/?EIO=4
[WS-Client][handleHeader]  - cKey: Sv0F7QyBpaxlkYxYn7hlQw==
[WS-Client][handleHeader] Server header:
[WS-Client][handleHeader]  - cCode: 200
[WS-Client][handleHeader]  - cIsUpgrade: 0
[WS-Client][handleHeader]  - cIsWebsocket: 0
[WS-Client][handleHeader]  - cAccept:
[WS-Client][handleHeader]  - cProtocol: arduino
[WS-Client][handleHeader]  - cExtensions:
[WS-Client][handleHeader]  - cVersion: 0
[WS-Client][handleHeader]  - cSessionId: ipvzuEETbfI-_H_lAAja
[WS-Client][handleHeader] found cSessionId
[WS-Client][sendHeader] sending header...
[WS-Client][sendHeader] handshake GET /socket.io/?EIO=4&transport=websocket&sid=ipvzuEETbfI-_H_lAAja HTTP/1.1
Host: 192.168.1.75:4000
Connection: Upgrade
Upgrade: websocket
Sec-WebSocket-Version: 13
Sec-WebSocket-Key: xUMPRHBepIKukffJXfKQLw==
Sec-WebSocket-Protocol: arduino
origin: http://192.168.1.80
User-Agent: arduino-WebSocket-Client

[write] n: 317 t: 1512265
[WS-Client][sendHeader] sending header... Done (34873us).
[WS-Client][handleHeader] RX: HTTP/1.1 101 Switching Protocols
[WS-Client][handleHeader] RX: Upgrade: websocket
[WS-Client][handleHeader] RX: Connection: Upgrade
[WS-Client][handleHeader] RX: Sec-WebSocket-Accept: fMrX17J3Pd1GVE5yYDwKgUz7CNE=
[WS-Client][handleHeader] RX: Sec-WebSocket-Protocol: arduino
[WS-Client][handleHeader] Header read fin.
[WS-Client][handleHeader] Client settings:
[WS-Client][handleHeader]  - cURL: /socket.io/?EIO=4
[WS-Client][handleHeader]  - cKey: xUMPRHBepIKukffJXfKQLw==
[WS-Client][handleHeader] Server header:
[WS-Client][handleHeader]  - cCode: 101
[WS-Client][handleHeader]  - cIsUpgrade: 1
[WS-Client][handleHeader]  - cIsWebsocket: 1
[WS-Client][handleHeader]  - cAccept: fMrX17J3Pd1GVE5yYDwKgUz7CNE=
[WS-Client][handleHeader]  - cProtocol: arduino
[WS-Client][handleHeader]  - cExtensions:
[WS-Client][handleHeader]  - cVersion: 0
[WS-Client][handleHeader]  - cSessionId: ipvzuEETbfI-_H_lAAja
[WS-Client][handleHeader] Websocket connection init done.
[WS][0][headerDone] Header Handling Done.
[wsIOc] Connected to url: /socket.io/?EIO=4
[WS][0][sendFrame] ------- send message frame -------
[WS][0][sendFrame] fin: 1 opCode: 1 mask: 1 length: 6 headerToPayload: 0
[WS][0][sendFrame] text: 2probe
[WS][0][sendFrame] pack to one TCP package...
[write] n: 12 t: 1512392
[WS][0][sendFrame] sending Frame Done (3332us).
[WS][0][sendFrame] ------- send message frame -------
[WS][0][sendFrame] fin: 1 opCode: 1 mask: 1 length: 1 headerToPayload: 1
[WS][0][sendFrame] text: 5
[write] n: 7 t: 1512413
[WS][0][sendFrame] sending Frame Done (3104us).
[IOc] Connected to url: /socket.io/?EIO=4
[write] n: 6 t: 1512421
[write] n: 2 t: 1512427
[write] n: 33 t: 1512430
[WS][0][handleWebsocketWaitFor] size: 2 cWsRXsize: 0
[readCb] n: 2 t: 1512439
[WS][0][handleWebsocketWaitFor][readCb] size: 2 ok: 1
[WS][0][handleWebsocket] ------- read massage frame -------
[WS][0][handleWebsocket] fin: 1 rsv1: 0 rsv2: 0 rsv3 0  opCode: 1
[WS][0][handleWebsocket] mask: 0 payloadLen: 6
[readCb] n: 6 t: 1512461
[WS][0][handleWebsocket] text: 3probe
[wsIOc] get pong
[WS][0][handleWebsocketWaitFor] size: 2 cWsRXsize: 0
[readCb] n: 2 t: 1512474
[WS][0][handleWebsocketWaitFor][readCb] size: 2 ok: 1
[WS][0][handleWebsocket] ------- read massage frame -------
[WS][0][handleWebsocket] fin: 1 rsv1: 0 rsv2: 0 rsv3 0  opCode: 8
[WS][0][handleWebsocket] mask: 0 payloadLen: 0
[WS][0][handleWebsocket] get ask for close. Code: 1000

[WS][0][handleWebsocket] clientDisconnect code: 1000
[WS][0][sendFrame] ------- send message frame -------
[WS][0][sendFrame] fin: 1 opCode: 8 mask: 1 length: 2 headerToPayload: 0
[WS][0][sendFrame] pack to one TCP package...
[write] n: 8 t: 1512521
[WS][0][sendFrame] sending Frame Done (3144us).
[WS-Client] client disconnected.
[IOc] Disconnected!

Anything else I'm looking forward to hearing from you

[Links2004]

can you try with the latest master?
this looks like its may the same as #611

[joelzavala]

I'm working with version 2.3.4, am I going back to 2.3.3?

[Links2004]

so you are on the master branch?
since based on the log you dont have the EIO=4 detect fix.

arduinoWebSockets/src/SocketIOclient.cpp

Lines 69 to 74 in a484da4

	void SocketIOclient::initClient(void) {
	if(_client.cUrl.indexOf("EIO=4") != -1) {
	DEBUG_WEBSOCKETS("[wsIOc] found EIO=4 disable EIO ping on client\n");
	configureEIOping(true);
	}
	}

[joelzavala]

I installed 2.3.3 and I see that it does not have the initClient function. I installed it in platformio

[Links2004]

I released https://github.com/Links2004/arduinoWebSockets/releases/tag/2.3.4 that will make it easier for platformio

[joelzavala]

I tried both and 2.3.3 and 2.3.4 give me the same problem

[Links2004]

can you post the log for 2.3.4 with the found EIO=4 disable EIO ping on client

[joelzavala]

[WS-Client] Websocket Version: 2.3.4
[wsIOc] found EIO=4 disable EIO ping on client
[WS-Client] connect ws...
[WS-Client] connected to 192.168.1.75:4000.
[WS-Client][sendHeader] sending header...
[WS-Client][sendHeader] handshake GET /socket.io/?EIO=4&transport=polling HTTP/1.1
Host: 192.168.1.75:4000
Connection: keep-alive
Origin: file://
User-Agent: arduino-WebSocket-Client

[write] n: 156 t: 5327
[WS-Client][sendHeader] sending header... Done (20272us).
[WS-Client][handleHeader] RX: HTTP/1.1 200 OK
[WS-Client][handleHeader] RX: Access-Control-Allow-Origin: *
[WS-Client][handleHeader] RX: Content-Type: text/plain; charset=UTF-8
[WS-Client][handleHeader] RX: Content-Length: 96
[WS-Client][handleHeader] RX: Date: Tue, 09 Feb 2021 17:40:56 GMT
[WS-Client][handleHeader] RX: Connection: keep-alive
[WS-Client][handleHeader] RX: Keep-Alive: timeout=5
[WS-Client][handleHeader] Header read fin.
[WS-Client][handleHeader] Client settings:
[WS-Client][handleHeader]  - cURL: /socket.io/?EIO=4
[WS-Client][handleHeader]  - cKey: 0+EUMBb3MQ2gRt0BeWuOCw==
[WS-Client][handleHeader] Server header:
[WS-Client][handleHeader]  - cCode: 200
[WS-Client][handleHeader]  - cIsUpgrade: 0
[WS-Client][handleHeader]  - cIsWebsocket: 1
[WS-Client][handleHeader]  - cAccept:
[WS-Client][handleHeader]  - cProtocol: arduino
[WS-Client][handleHeader]  - cExtensions:
[WS-Client][handleHeader]  - cVersion: 0
[WS-Client][handleHeader]  - cSessionId:
[WS-Client][handleHeader] still missing cSessionId try socket.io V3
[WS-Client][handleHeader] socket.io json: 0{"sid":"5m7lV31QsyPwGEr2AAXM","upgrades":["websocket"],"pingInterval":25000,"pingTimeout":5000}
[WS-Client][handleHeader]  - cSessionId: 5m7lV31QsyPwGEr2AAXM
[WS-Client][handleHeader] Header read fin.
[WS-Client][handleHeader] Client settings:
[WS-Client][handleHeader]  - cURL: /socket.io/?EIO=4
[WS-Client][handleHeader]  - cKey: 0+EUMBb3MQ2gRt0BeWuOCw==
[WS-Client][handleHeader] Server header:
[WS-Client][handleHeader]  - cCode: 200
[WS-Client][handleHeader]  - cIsUpgrade: 0
[WS-Client][handleHeader]  - cIsWebsocket: 1
[WS-Client][handleHeader]  - cAccept:
[WS-Client][handleHeader]  - cProtocol: arduino
[WS-Client][handleHeader]  - cExtensions:
[WS-Client][handleHeader]  - cVersion: 0
[WS-Client][handleHeader]  - cSessionId: 5m7lV31QsyPwGEr2AAXM
[WS-Client][handleHeader] found cSessionId
[WS-Client][sendHeader] sending header...
[WS-Client][sendHeader] handshake GET /socket.io/?EIO=4&transport=websocket&sid=5m7lV31QsyPwGEr2AAXM HTTP/1.1
Host: 192.168.1.75:4000
Connection: Upgrade
Upgrade: websocket
Sec-WebSocket-Version: 13
Sec-WebSocket-Key: mieRklpsTnwYR6WDuRzvdQ==
Sec-WebSocket-Protocol: arduino
Origin: file://
User-Agent: arduino-WebSocket-Client

[write] n: 305 t: 5542
[WS-Client][sendHeader] sending header... Done (33615us).
[WS-Client][handleHeader] RX: HTTP/1.1 101 Switching Protocols
[WS-Client][handleHeader] RX: Upgrade: websocket
[WS-Client][handleHeader] RX: Connection: Upgrade
[WS-Client][handleHeader] RX: Sec-WebSocket-Accept: uanNFG15dd0V0a6UcHBoL/CqpyM=
[WS-Client][handleHeader] RX: Sec-WebSocket-Protocol: arduino
[WS-Client][handleHeader] Header read fin.
[WS-Client][handleHeader] Client settings:
[WS-Client][handleHeader]  - cURL: /socket.io/?EIO=4
[WS-Client][handleHeader]  - cKey: mieRklpsTnwYR6WDuRzvdQ==
[WS-Client][handleHeader] Server header:
[WS-Client][handleHeader]  - cCode: 101
[WS-Client][handleHeader]  - cIsUpgrade: 1
[WS-Client][handleHeader]  - cIsWebsocket: 1
[WS-Client][handleHeader]  - cAccept: uanNFG15dd0V0a6UcHBoL/CqpyM=
[WS-Client][handleHeader]  - cProtocol: arduino
[WS-Client][handleHeader]  - cExtensions:
[WS-Client][handleHeader]  - cVersion: 0
[WS-Client][handleHeader]  - cSessionId: 5m7lV31QsyPwGEr2AAXM
[WS-Client][handleHeader] Websocket connection init done.
[WS][0][headerDone] Header Handling Done.
[wsIOc] Connected to url: /socket.io/?EIO=4
[WS][0][sendFrame] ------- send message frame -------
[WS][0][sendFrame] fin: 1 opCode: 1 mask: 1 length: 6 headerToPayload: 0
[WS][0][sendFrame] text: 2probe
[WS][0][sendFrame] pack to one TCP package...
[write] n: 12 t: 5671
[WS][0][sendFrame] sending Frame Done (3041us).
[WS][0][sendFrame] ------- send message frame -------
[WS][0][sendFrame] fin: 1 opCode: 1 mask: 1 length: 1 headerToPayload: 1
[WS][0][sendFrame] text: 5
[write] n: 7 t: 5692
[WS][0][sendFrame] sending Frame Done (2664us).
[IOc] Connected to url: /socket.io/?EIO=4
[write] n: 6 t: 5699
[write] n: 2 t: 5705
[write] n: 9 t: 5708
[WS][0][handleWebsocketWaitFor] size: 2 cWsRXsize: 0
[readCb] n: 2 t: 5715
[WS][0][handleWebsocketWaitFor][readCb] size: 2 ok: 1
[WS][0][handleWebsocket] ------- read massage frame -------
[WS][0][handleWebsocket] fin: 1 rsv1: 0 rsv2: 0 rsv3 0  opCode: 1
[WS][0][handleWebsocket] mask: 0 payloadLen: 6
[readCb] n: 6 t: 5738
[WS][0][handleWebsocket] text: 3probe
[wsIOc] get pong
[WS][0][handleWebsocketWaitFor] size: 2 cWsRXsize: 0
[readCb] n: 2 t: 5750
[WS][0][handleWebsocketWaitFor][readCb] size: 2 ok: 1
[WS][0][handleWebsocket] ------- read massage frame -------
[WS][0][handleWebsocket] fin: 1 rsv1: 0 rsv2: 0 rsv3 0  opCode: 8
[WS][0][handleWebsocket] mask: 0 payloadLen: 0
[WS][0][handleWebsocket] get ask for close. Code: 1000

[WS][0][handleWebsocket] clientDisconnect code: 1000
[WS][0][sendFrame] ------- send message frame -------
[WS][0][sendFrame] fin: 1 opCode: 8 mask: 1 length: 2 headerToPayload: 0
[WS][0][sendFrame] pack to one TCP package...
[write] n: 8 t: 5797
[WS][0][sendFrame] sending Frame Done (2786us).
[WS-Client] client disconnected.
[IOc] Disconnected!
[wsIOc] Disconnected!

and repeats itself

[WS-Client] connect ws...
[WS-Client] connected to 192.168.1.75:4000.
[WS-Client][sendHeader] sending header...
[WS-Client][sendHeader] handshake GET /socket.io/?EIO=4&transport=polling HTTP/1.1
Host: 192.168.1.75:4000
Connection: keep-alive
Origin: file://
User-Agent: arduino-WebSocket-Client

[write] n: 156 t: 6343
[WS-Client][sendHeader] sending header... Done (20424us).
[WS-Client][handleHeader] RX: HTTP/1.1 200 OK
[WS-Client][handleHeader] RX: Access-Control-Allow-Origin: *
[WS-Client][handleHeader] RX: Content-Type: text/plain; charset=UTF-8
[WS-Client][handleHeader] RX: Content-Length: 96
[WS-Client][handleHeader] RX: Date: Tue, 09 Feb 2021 17:40:57 GMT
[WS-Client][handleHeader] RX: Connection: keep-alive
[WS-Client][handleHeader] RX: Keep-Alive: timeout=5
[WS-Client][handleHeader] Header read fin.
[WS-Client][handleHeader] Client settings:
[WS-Client][handleHeader]  - cURL: /socket.io/?EIO=4
[WS-Client][handleHeader]  - cKey: vVGl5sgzO3zIFtaCGa7e7A==
[WS-Client][handleHeader] Server header:
[WS-Client][handleHeader]  - cCode: 200
[WS-Client][handleHeader]  - cIsUpgrade: 0
[WS-Client][handleHeader]  - cIsWebsocket: 0
[WS-Client][handleHeader]  - cAccept: 
[WS-Client][handleHeader]  - cProtocol: arduino
[WS-Client][handleHeader]  - cExtensions:
[WS-Client][handleHeader]  - cVersion: 0
[WS-Client][handleHeader]  - cSessionId:
[WS-Client][handleHeader] still missing cSessionId try socket.io V3
[WS-Client][handleHeader] socket.io json: 0{"sid":"HyNakuYC2REoHd5XAAXN","upgrades":["websocket"],"pingInterval":25000,"pingTimeout":5000}
[WS-Client][handleHeader]  - cSessionId: HyNakuYC2REoHd5XAAXN
[WS-Client][handleHeader] Header read fin.
[WS-Client][handleHeader] Client settings:
[WS-Client][handleHeader]  - cURL: /socket.io/?EIO=4
[WS-Client][handleHeader]  - cKey: vVGl5sgzO3zIFtaCGa7e7A==
[WS-Client][handleHeader] Server header:
[WS-Client][handleHeader]  - cCode: 200
[WS-Client][handleHeader]  - cIsUpgrade: 0
[WS-Client][handleHeader]  - cIsWebsocket: 0
[WS-Client][handleHeader]  - cAccept:
[WS-Client][handleHeader]  - cProtocol: arduino
[WS-Client][handleHeader]  - cExtensions:
[WS-Client][handleHeader]  - cVersion: 0
[WS-Client][handleHeader]  - cSessionId: HyNakuYC2REoHd5XAAXN
[WS-Client][handleHeader] found cSessionId
[WS-Client][sendHeader] sending header...
[WS-Client][sendHeader] handshake GET /socket.io/?EIO=4&transport=websocket&sid=HyNakuYC2REoHd5XAAXN HTTP/1.1
Host: 192.168.1.75:4000
Connection: Upgrade
Upgrade: websocket
Sec-WebSocket-Version: 13
Sec-WebSocket-Key: 057CXFl4yfSlkMt1rcIEQg==
Sec-WebSocket-Protocol: arduino
Origin: file://
User-Agent: arduino-WebSocket-Client

[write] n: 305 t: 6560
[WS-Client][sendHeader] sending header... Done (33621us).
[WS-Client][handleHeader] RX: HTTP/1.1 101 Switching Protocols
[WS-Client][handleHeader] RX: Upgrade: websocket
[WS-Client][handleHeader] RX: Connection: Upgrade
[WS-Client][handleHeader] RX: Sec-WebSocket-Accept: C0zRsRtNcyYn0CPvZB9sJrDzJhU=
[WS-Client][handleHeader] RX: Sec-WebSocket-Protocol: arduino
[WS-Client][handleHeader] Header read fin.
[WS-Client][handleHeader] Client settings:
[WS-Client][handleHeader]  - cURL: /socket.io/?EIO=4
[WS-Client][handleHeader]  - cKey: 057CXFl4yfSlkMt1rcIEQg==
[WS-Client][handleHeader] Server header:
[WS-Client][handleHeader]  - cCode: 101
[WS-Client][handleHeader]  - cIsUpgrade: 1
[WS-Client][handleHeader]  - cIsWebsocket: 1
[WS-Client][handleHeader]  - cAccept: C0zRsRtNcyYn0CPvZB9sJrDzJhU=
[WS-Client][handleHeader]  - cProtocol: arduino
[WS-Client][handleHeader]  - cExtensions:
[WS-Client][handleHeader]  - cVersion: 0
[WS-Client][handleHeader]  - cSessionId: HyNakuYC2REoHd5XAAXN
[WS-Client][handleHeader] Websocket connection init done.
[WS][0][headerDone] Header Handling Done.
[wsIOc] Connected to url: /socket.io/?EIO=4
[WS][0][sendFrame] ------- send message frame -------
[WS][0][sendFrame] fin: 1 opCode: 1 mask: 1 length: 6 headerToPayload: 0
[WS][0][sendFrame] text: 2probe
[WS][0][sendFrame] pack to one TCP package...
[write] n: 12 t: 6688
[WS][0][sendFrame] sending Frame Done (3094us).
[WS][0][sendFrame] ------- send message frame -------
[WS][0][sendFrame] fin: 1 opCode: 1 mask: 1 length: 1 headerToPayload: 1
[WS][0][sendFrame] text: 5
[write] n: 7 t: 6710
[WS][0][sendFrame] sending Frame Done (2575us).
[IOc] Connected to url: /socket.io/?EIO=4
[write] n: 6 t: 6717
[write] n: 2 t: 6723
[write] n: 9 t: 6725
[WS][0][handleWebsocketWaitFor] size: 2 cWsRXsize: 0
[readCb] n: 2 t: 6733
[WS][0][handleWebsocketWaitFor][readCb] size: 2 ok: 1
[WS][0][handleWebsocket] ------- read massage frame -------
[WS][0][handleWebsocket] fin: 1 rsv1: 0 rsv2: 0 rsv3 0  opCode: 1
[WS][0][handleWebsocket] mask: 0 payloadLen: 6
[readCb] n: 6 t: 6756
[WS][0][handleWebsocket] text: 3probe
[wsIOc] get pong
[WS][0][handleWebsocketWaitFor] size: 2 cWsRXsize: 0
[readCb] n: 2 t: 6768
[WS][0][handleWebsocketWaitFor][readCb] size: 2 ok: 1
[WS][0][handleWebsocket] ------- read massage frame -------
[WS][0][handleWebsocket] fin: 1 rsv1: 0 rsv2: 0 rsv3 0  opCode: 8
[WS][0][handleWebsocket] mask: 0 payloadLen: 0
[WS][0][handleWebsocket] get ask for close. Code: 1000

[WS][0][handleWebsocket] clientDisconnect code: 1000
[WS][0][sendFrame] ------- send message frame -------
[WS][0][sendFrame] fin: 1 opCode: 8 mask: 1 length: 2 headerToPayload: 0
[WS][0][sendFrame] pack to one TCP package...
[write] n: 8 t: 6816
[WS][0][sendFrame] sending Frame Done (2580us).
[WS-Client] client disconnected.
[IOc] Disconnected!
[wsIOc] Disconnected!

[Links2004]

ok, thanks, are you sure that your data string is correct for me it looks like you include the engineIO and socketIO message types (the numbers) which will be included by the lib automatically, do you have them from a browser network log or something?

may try:

            String data = "/switch,{\"device\":\"";
            data += serial;
            data += "\"}";

arduinoWebSockets/src/SocketIOclient.h

Lines 18 to 36 in f55bf8d

	typedef enum {
	eIOtype_OPEN = '0', ///< Sent from the server when a new transport is opened (recheck)
	eIOtype_CLOSE = '1', ///< Request the close of this transport but does not shutdown the connection itself.
	eIOtype_PING = '2', ///< Sent by the client. Server should answer with a pong packet containing the same data
	eIOtype_PONG = '3', ///< Sent by the server to respond to ping packets.
	eIOtype_MESSAGE = '4', ///< actual message, client and server should call their callbacks with the data
	eIOtype_UPGRADE = '5', ///< Before engine.io switches a transport, it tests, if server and client can communicate over this transport. If this test succeed, the client sends an upgrade packets which requests the server to flush its cache on the old transport and switch to the new transport.
	eIOtype_NOOP = '6', ///< A noop packet. Used primarily to force a poll cycle when an incoming websocket connection is received.
	} engineIOmessageType_t;
	typedef enum {
	sIOtype_CONNECT = '0',
	sIOtype_DISCONNECT = '1',
	sIOtype_EVENT = '2',
	sIOtype_ACK = '3',
	sIOtype_ERROR = '4',
	sIOtype_BINARY_EVENT = '5',
	sIOtype_BINARY_ACK = '6',
	} socketIOmessageType_t;

[joelzavala]

to connect to the default namespace I do this

String data = "40{\"device\": \"";
data + = serial;
data + = "\"} ";
// String data = "40/switch";
socket.send (sIOtype_CONNECT, data);

and it works fine, but it is already working, thank you very much :)

[Duko]

Looks like the namespace is not saved for later messages

Server Side:

socketIO.send(sIOtype_CONNECT, "/test");

// server address, port and URL
socketIO.begin("...", 3000, "/socket.io/?EIO=4");